Applicant claims, under 35 U.S.C. xc2xa7119, the benefit of priority of the filing date of Mar. 29, 1999 of a German patent application, copy attached, Serial Number 199 14 311.0, filed on the aforementioned date, the entire contents of which is incorporated herein by reference.
1. Field of the Invention
The invention relates to a process for attaching a scale or scale carrier of a length measuring system, as well as to a device designed for this purpose.
2. Discussion of Related Art
Very long scales are often required on machine tools or coordinate measuring machines for position measuring. These scales must be fastened so that they are oriented parallel in relation to the measuring direction, wherein the measuring direction is fixed by the guide of the machine tool or measuring machine.
Various methods for attaching scales have already been proposed. In accordance with EP 0 388 453 B1, a self-adhering tape scale is glued on by an applicator and is oriented in relation to the guided running of a carriage of a machine tool or a measuring machine. This type of fastening provides a good coordination between the measuring tape and the scanning head, but can only be employed in connection with highly elastic scales in the form of tapes.
A step is described in DE 197 00 367 A1, in accordance with which, for aligning a measuring tape, lateral contact elements are fastened along the length of the measuring tape, against which the measuring tape is placed.
A type of fastening for thin measuring tapes, which is also widely used, has in its longitudinal extension the measuring tape is received in a groove. This is described on pages 58 and 59 of the September 1998 company publication xe2x80x9cNC Laxc3xa4ngenme systemexe2x80x9d [NC Length Measuring Systems] of the Dr. Johannes Heidenhain GmbH. In accordance with this, profiled receivers made of extruded aluminum are fastened on a fastening surface by a tape which is adhesive on two sides, and thereafter the measuring tape is pushed into the receiving groove of the profiled section. Here, too, the problem lies in aligning the profiled receiving section exactly parallel in respect to the measuring direction.
With adhesive fastening of a scale or a scale carrier there is the general problem of the adhesive force of the glue being so great that an alignment is no longer possible after the surfaces to be connected have been brought into contact with each other. The methods for alignment known so far are particularly suited for flexible measuring tapes. Scales as well as scale carriersxe2x80x94in particular profiled receiversxe2x80x94which are relatively inherently stable are difficult to fasten in an aligned manner by the known methods.
An object of the invention is therefore based on disclosing a process and a device, by which even scales or scale carriers which are relatively inherently stable can be aligned in a simple manner and glued to a body.
The above object is attained by a process for the attachment of a scale component of a length measuring system to a mounting surface of a first body in a directional manner, wherein a second body is arranged to be displaceable in relation to the first body in a measuring direction, wherein the attachment takes place by an adhesive. The process includes supporting the scale component by at least one spacer so that the scale is held spaced apart from the mounting surface, aligning the scale component on the mounting surface in this position by displacing the spacer, removing the at least one spacer at the end of the aligning process; and moving the scale component in the direction of the mounting surface in order to make the holding force of the adhesive between the aligned scale component and the mounting surface effective.
The above object is also attained by a device for the attachment of a scale component of a length measuring system to a mounting surface of a first body, wherein a second body is arranged to be displaceable in relation to the first body in a measuring direction, wherein an adhesive layer is provided between the scale component and the mounting surface. The device includes at least one spacer that holds the scale component and supports the scale component at a distance from the mounting surface and is displaceably mounted on the mounting surface for alignment; and wherein the at least one spacer is actuated to remove the support and to make the holding force of the adhesive layer between the scale component and the mounting surface effective.
Details of the invention will be further explained in what follows by means of the embodiment represented in the drawings.